GND, which is one of the enzymes in the pentose phosphate cycle, oxidizes and decarboxylates 6-phosphogluconic acid to form D-ribulose-5-phosphate.
As the DNAs encoding GND, those derived from Escherichia coli [Gene, 27, 253 (1984)], Bacillus subtilis [J. Biol. Chem., 261, 13744 (1986)], etc. have been isolated and their nucleotide sequences have been reported.
With regard to microorganisms belonging to the genus Corynebacterium, there are reports on GND of Corynebacterium glutamicum disclosing the biochemical properties and the nucleotide sequences of genes encoding GND [Agric. Biol. Chem., 51, 1257 (1987); Eur. J. Biochem., 267, 3442 (2000); Enzyme Microb. Technol., 28, 754 (2001); Japanese Published Unexamined Patent Application No. 224662/97; EP1108790].
However, it is not known yet that introduction of a mutation into DNA encoding GND can enhance the productivity of metabolites. Further, there is no report that describes or suggests what mutation should be introduced into DNA encoding GND to obtain the above effect.